The objective of this study is to a) evaluate the effect on initiation and progression of dental caries when carious and non-carious occlusal pits and fissures are sealed with an ultraviolet light polymerized sealant, NuvasealR, for time period up to five years, b) compare the costs and benefits of that procedure to the use of conventional restorative techniques, and, c) compare the efficacy of an ultraviolet light polymerized sealant, NuvasealR, with an autopolymerized sealant, DeltonR, in regard to objectives (a) and (b). Children from 5-15 years of age will have all previously untreated non-carious and carious (no greater than one half dentin penetration) occlusal surfaces of permanent posterior teeth sealed with either Nuvaseal R or DeltonR. A third treatment regimen will restore only carious occlusal surfaces with amalgam. Permanent occlusal surfaces with deeper caries penetration and all other surfaces of permanent and deciduous teeth will be restored with conventional filling materials when indicated. The initiation of new carious lesions and the progress of existing lesions will be evaluated clinically and radiographically. The costs and the benefits of sealants and traditional restorative procedures will be compared over a period of time that would enable the determination of the impact of proximal caries. NuvasealR and DeltonR will be compared with regard to retention rate, effect on initiation and progress of caries, and comparative time and ease of application.